[Iberogast: a modern phytotherapeutic combined herbal drug for the treatment of functional disorders of the gastrointestinal tract (dyspepsia, irritable bowel syndrome)--from phytomedicine to "evidence based phytotherapy." A systematic review]

Gastroparesis syndromes: emerging drug targets and potential therapeutic opportunities

INTRODUCTION

Gastroparesis (Gp) and related disorders such as chronic unexplained nausea and vomiting and functional dyspepsia, known as gastropareis syndromes (GpS), have large unmet needs. Mainstays of GpS treatments are diet and drugs.

AREAS COVERED

The purpose of this review is to explore potential new medications and other therapies for gastroparesis. Before discussing possible new drugs, the currently used drugs are discussed. These include dopamine receptor antagonists, 5-hydroxytryptamine receptor agonists and antagonists, neurokinin-1 receptor antagonists and other anti-emetics. The article also considers future drugs that may be used for Gp, based on currently known pathophysiology.

EXPERT OPINION

Gaps in knowledge about the pathophysiology of gastroparesis and related syndromes are critical to developing therapeutic agents that will be successful. Recent major developments in the gastroparesis arena are related to microscopic anatomy, cellular function, and pathophysiology. The major challenges moving forward will be to develop the genetic and biochemical correlates of these major developments in gastroparesis research.

Herbal Preparation STW 5 for Functional Gastrointestinal Disorders: Clinical Experience in Everyday Practice

BACKGROUND

The most common functional gastrointestinal disorders (FGID) are functional dyspepsia (FD) and irritable bowel syndrome (IBS), with a prevalence in the general population of 15-20% (FD) and 10% (IBS), respectively. The complexity of pathophysiologic mechanisms and limitations in therapeutic options make the management of FD and IBS patients a challenge in routine clinical practice.

SUMMARY

Syndromes classified as FGID frequently overlap, and coexist with gastroesophageal reflux disease (GERD). Patients with overlapping symptoms are more likely to seek medical care. The challenge for routine clinical practice is to find the best approach for treatment of multiple symptoms. STW 5, a combination of 9 herbal extracts, was shown to have multi-target effects: it normalizes the disturbed gastrointestinal motility, alleviates hypersensitivity, inhibits inflammation, suppresses gastric hypersecretion, and modulates the microbiota. Controlled randomized studies proved STW 5 to be efficacious both in FD and IBS, with control over the full spectrum of upper and lower gastrointestinal symptoms. STW 5 reduced concomitant heartburn in FD patients. STW 5 was well tolerated in the examined populations, independent of concomitant diseases and concomitant medication. Key Messages: The clinical use of the herbal preparation STW 5 in FD and IBS is evidence-based. STW 5 is an example for the concept of multi-target therapy. It offers treatment opportunities in routine clinical practice with high prevalence of overlap of FGID and concomitant GERD. Considering that FD and IBS are typically chronic and recurrent conditions, the clinically observed good tolerability and safety of STW 5 is an advantage.

Medicinal plants--prophylactic and therapeutic options for gastrointestinal and respiratory diseases in calves and piglets? A systematic review

BACKGROUND

Gastrointestinal and respiratory diseases in calves and piglets lead to significant economic losses in livestock husbandry. A high morbidity has been reported for diarrhea (calves ≤ 35%; piglets ≤ 50%) and for respiratory diseases (calves ≤ 80%; piglets ≤ 40%). Despite a highly diverse etiology and pathophysiology of these diseases, treatment with antimicrobials is often the first-line therapy. Multi-antimicrobial resistance in pathogens results in international accordance to strengthen the research in novel treatment options. Medicinal plants bear a potential as alternative or additional treatment. Based on the versatile effects of their plant specific multi-component-compositions, medicinal plants can potentially act as 'multi-target drugs'. Regarding the plurality of medicinal plants, the aim of this systematic review was to identify potential medicinal plant species for prevention and treatment of gastrointestinal and respiratory diseases and for modulation of the immune system and inflammation in calves and piglets.

RESULTS

Based on nine initial sources including standard textbooks and European ethnoveterinary studies, a total of 223 medicinal plant species related to the treatment of gastrointestinal and respiratory diseases was identified. A defined search strategy was established using the PRISMA statement to evaluate 30 medicinal plant species starting from 20'000 peer-reviewed articles published in the last 20 years (1994-2014). This strategy led to 418 references (257 in vitro, 84 in vivo and 77 clinical trials, thereof 48 clinical trials in veterinary medicine) to evaluate effects of medicinal plants and their efficacy in detail. The findings indicate that the most promising candidates for gastrointestinal diseases are Allium sativum L., Mentha x piperita L. and Salvia officinalis L.; for diseases of the respiratory tract Echinacea purpurea (L.) MOENCH, Thymus vulgaris L. and Althea officinalis L. were found most promising, and Echinacea purpurea (L.) MOENCH, Camellia sinensis (L.) KUNTZE, Glycyrrhiza glabra L. and Origanum vulgare L. were identified as best candidates for modulation of the immune system and inflammation.

CONCLUSIONS

Several medicinal plants bear a potential for novel treatment strategies for young livestock. There is a need for further research focused on gastrointestinal and respiratory diseases in calves and piglets, and the findings of this review provide a basis on plant selection for future studies.

Multicomponent phytotherapeutic approach gaining momentum: Is the "one drug to fit all" model breaking down?

Natural product based drugs constitute a substantial proportion of the pharmaceutical market particularly in the therapeutic areas of infectious diseases and oncology. The primary focus of any drug development program so far has been to design selective ligands (drugs) that act on single selective disease targets to obtain highly efficacious and safe drugs with minimal side effects. Although this approach has been successful for many diseases, yet there is a significant decline in the number of new drug candidates being introduced into clinical practice over the past few decades. This serious innovation deficit that the pharmaceutical industries are facing is due primarily to the post-marketing failures of blockbuster drugs. Many analysts believe that the current capital-intensive model-"the one drug to fit all" approach will be unsustainable in future and that a new "less investment, more drugs" model is necessary for further scientific growth. It is now well established that many diseases are multi-factorial in nature and that cellular pathways operate more like webs than highways. There are often multiple ways or alternate routes that may be switched on in response to the inhibition of a specific target. This gives rise to the resistant cells or resistant organisms under the specific pressure of a targeted agent, resulting in drug resistance and clinical failure of the drug. Drugs designed to act against individual molecular targets cannot usually combat multifactorial diseases like cancer, or diseases that affect multiple tissues or cell types such as diabetes and immunoinflammatory diseases. Combination drugs that affect multiple targets simultaneously are better at controlling complex disease systems and are less prone to drug resistance. This multicomponent therapy forms the basis of phytotherapy or phytomedicine where the holistic therapeutic effect arises as a result of complex positive (synergistic) or negative (antagonistic) interactions between different components of a cocktail. In this approach, multicomponent therapy is considered to be advantageous for multifactorial diseases, instead of a "magic bullet" the metaphor of a "herbal shotgun" might better explain the state of affairs. The different interactions between various components might involve the protection of an active substance from decomposition by enzymes, modification of transport across membranes of cells or organelles, evasion of multidrug resistance mechanisms among others.

Investigation of STW 5 (Iberogast®) preventive effects in experimental sepsis

CONTEXT

STW 5 (Iberogast(®)) is a well known herbal combination drug containing glycosides and flavonoids for which multiple pharmacological properties have been shown.

OBJECTIVE

In this study, attempts were made to assess whether STW 5, an aqueous ethanol solution, has a preventive effect against liver and lung pathological damage in rats after experimental induction of sepsis [cecal ligation and puncture (CLP)].

MATERIALS AND METHODS

Experimental sepsis was induced in rats using CLP operation. The rats (n = 36) were divided into six groups (six/group): Sham-operated (SOP); CLP; CLP + STW 5 (2.5, 5 and 10 mg/kg) and CLP + indomethacin. The drugs were injected intraperitoneally immediately after sepsis induction.

RESULTS

It was found that induction of sepsis 24 h after CLP was associated with significant liver and lung damage, also remaining after STW 5 administration.

DISCUSSION AND CONCLUSION

It appears that STW 5, which has a pronounced efficacy in functional gastro-intestinal diseases, has no effect on septic liver and lung damage in the CLP rat model.

Phytotherapy of chronic abdominal pain following pancreatic carcinoma surgery: a single case observation

A patient with pancreatic carcinoma diagnosed in 2005 suffered from chronic abdominal pain 6 years later that did not respond to conventional pain treatment according to guidelines. Furthermore, several complementary medical approaches remained ineffective. In the long run, only an Iberis amara drug combination relieved pain sufficiently. The drug is registered in Germany for the indications irritable bowel syndrome and dyspepsia. The multi-target approach of this combination drug may account for the effectiveness under these fundamentally different pathophysiological conditions. No serious undesired effects have been described in the use of this drug for other indications and none were observed in this case.

STW 5/Iberogast: Multi-Target-Wirkung bei funktioneller Dyspepsie und Reizdarmsyndrom

Functional gastro-intestinal diseases such as functional dyspepsia and irritable bowel syndrome are a therapeutic challenge, as they are not only characterized by a multitude of symptoms, some of them with severe consequences for affected patients, but are also caused by a multitude of factors. The clinical efficacy of the therapeutics STW 5/Iberogast in these diseases has been proven in a number of randomized prospective clinical studies. Several preclinical studies suggest that its efficacy could be due to its complex composition of nine standardized herbal extracts, which act differently on multiple sites. This principle, which is quite popular in clinical medicine, was introduced as a multi-target therapy for functional bowel disorders. Components of STW 5/Iberogast reduce gastro-intestinal hypersensitivity and act spasmolytic on spastic, tonicising on atonic gastro-intestinal muscle. In addition a stimulating effect on reduced mucus-secretion, an inhibitory effect on enhanced gastric acid secretion and an anti-inflammatory effect have been shown. These effects could explain the clinical efficacy of STW5/Iberogast in a large range of symptoms.

The active components and the pharmacological multi-target principle of STW 5 (Iberogast)

The therapeutic equivalence of the multi-herbal drug combination STW 5 (Iberogast) with two synthetic standard drugs can be explained by an additive or overadditive pharmacological synergism. A review of the different chemical constituents contained in this fixed combination of nine herbal drug extracts and their dominant mechanisms of action shows that they correlate very well with the clinically relevant overall pharmacological profile of the multi-herbal drug combination. This comprises modulatory effects on gastro-intestinal motility, anti-inflammatory action, inhibitory effects on gastric acid production and anti-oxidative and radical-inhibiting properties. As a multi-drug preparation with a multitude of therapeutic targets relevant in functional gastrointestinal diseases, its pharmacological profile of action in accordance with the multi-target principle.

Region-specific effects of STW 5 (Iberogast) and its components in gastric fundus, corpus and antrum

Functional dyspepsia (FD) is a disorder that involves impaired gastric accommodation, antral hypomotility, and upper abdominal pain. The herbal drug STW 5 (Iberogast) is used to successfully treat FD patients. Here, we report in vitro data revealing the mode of action of STW 5 and its individual herbal extracts on gastric motility. STW 5 evoked a relaxation of the proximal stomach but increased antral motility. Both effects are myogenic. The extracts of Angelica root, chamomile flower and liquorice root mimicked the inhibitory effects in the proximal stomach whereas the extracts of greater celandine herb, Melissa leaf, caraway fruit and bitter candy tuft increased motility of the proximal stomach. All extracts increased motility in the antrum comparable to the effects of STW 5. We conclude that the differential effects of STW 5 on proximal and distal stomach motor activity are not caused by solely spasmolytic or anti-spasmolytic effects of the individual components. It is suggested that the individual extracts target transduction mechanisms that are specifically expressed in the proximal vs. distal stomach. We present a rationale for the differential effect of STW 5 which is a result of the combined actions of its individual components and reason that the inhibitory effects in the proximal and the excitatory effects in the distal stomach may contribute to symptom relief in FD patients treated with STW 5 (Iberogast).

Binding of STW 5 (Iberogast) and its components to intestinal 5-HT, muscarinic M3, and opioid receptors

Clinical studies with the fixed herbal combination product STW 5 (Iberogast) have indicated an efficacy comparable to metoclopramide (5-HT(3) antagonist) and cisapride (5-HT(4) agonist) in functional gastro-intestinal diseases like functional dyspepsia (FD) and irritable bowel syndrome (IBS). Since serotonin (5-HT(3) and 5-HT(4)) and muscarinic M(3) receptors are known to play a central role in the etiology of FD and IBS, the extracts contained in STW 5 and several of their phytochemical components were studied in vitro for binding affinities to these receptors of the intestine. STW 5 inhibited the binding of (3)H-GR113808 and (3)H-4-DAMP to 5-HT(4) and M(3) receptors, respectively, about 10 times more potently than the binding of (3)H-GR65630 to 5-HT(3) receptors. IC(50) values for STW 5 did correspond to extract dilutions of 1:1000 (M(3) binding) and 1:2000 (5-HT(4) binding). In addition, STW 5 also potently inhibited the binding to opioid receptors with an IC(50) value of 1:2000. Of the nine herbal extracts contained in STW 5, the fresh plant extract of bitter candy tuft (Iberis amara) selectively inhibited binding to M(3) receptors, while ethanolic extracts of celandine herb and chamomile flower were selective to 5-HT(4), and liquorice root to 5-HT(3) receptors. Binding affinities to human recombinant 5-HT(3), 5-HT(4) and M(3) receptors were qualitatively similar to those of the corresponding intestinal receptors. The benzylisoquinoline alkaloid berberine had significant inhibitory action on 5-HT(4) and M(3) binding, showing IC(50) values of 40 ng/ml (100 nM) and 200 ng/ml (500 nM), respectively, but is present in the extract of celandine herb only in traces, so that also for the celandine extract a cooperative effect of several phytochemical constituents can be assumed. These in vitro data indicate that 5-HT(4) (to a lesser degree 5-HT(3)), muscarinic M(3), and opioid receptors represent target sites for the treatment of FD and IBS with STW 5 (Iberogast).

Phytotherapy for functional dyspepsia: a review of the clinical evidence for the herbal preparation STW 5

Functional gastrointestinal disorders such as functional (or non-ulcer) dyspepsia are characterized by a broad spectrum of symptoms referred to the upper abdomen without a detectable cause utilizing routine diagnostic measures. It is now believed that disordered gut function (including abnormalities like disturbances of motility such as postprandial fundic relaxation, gastric emptying and disturbed visceral sensory function) play a key role for the manifestation of these disorders. The underlying pathophysiology is not yet fully understood. However, the available data suggest that a number of factors may contribute to the manifestation of symptoms. These factors include environmental factors such as acute infections as trigger event, psychological stressors that may precede acute exacerbations and a genetic predisposition. Considering the large number of mechanisms, a treatment targeting a single mechanism is unlikely to be effective in all patients. Indeed, chemically defined treatments usually gain a 10-15% superiority over placebo. In recent years placebo-controlled studies have demonstrated superiority of a commercial multicomponent herbal preparation, STW 5, with the trade name Iberogast, for the treatment of patients with functional dyspepsia and irritable bowel syndrome. This phytopharmacon is a combination of nine plant extracts each with a number of different active constituents. Pharmacological studies have shown different effects of the single plant extracts on the (molecular) mechanisms which are discussed as underlying the manifestation of symptoms. Various well-controlled clinical trials have independently confirmed clinical efficacy and safety. The clinically efficacy of this multicomponent herbal preparation questions the current trend of highly targeted drug molecules that usually target one single receptor population while it has not been shown that a single receptor group plays a pivotal role for the control of symptoms. Herbal medicines are obtained from various plants and contain complex extracts with a large number of different active substances. While there are only limited head-to-head comparisons with conventional chemically defined medications, the combination of extracts with various gastrointestinal active ingredients appears to be advantageous for a heterogeneous condition such as functional dyspepsia.

The herbal preparation STW5 (lberogast) has potent and region-specific effects on gastric motility

Functional dyspepsia (FD) is amongst the most common functional gastrointestinal disorders. Symptomatic treatment includes the use of herbal preparations whose effects on gastric motility are unclear. The present study aimed at investigating the effects of STW 5 (Iberogast), a fixed combination of hydroethanolic herbal extracts, on gastric motility in vitro. Muscle strips from guinea-pig gastric fundus, corpus and antrum were set up in organ baths either in circular or longitudinal orientation. Addition of ethanol-free STW 5 to the organ baths (32-512 microg mL(-1)) dose-dependently evoked a sustained and reversible relaxation of circular and longitudinal fundus and corpus muscle strips without changes in phasic activity. In contrast, antral muscle strips responded to STW 5 with a significant increase in the contractile force of phasic contractions without changes in tone. All effects were resistant to tetrodotoxin (0.5 micromol L(-1)), atropine (1 micromol L(-1)), omega-conotoxin GVIA (0.5 micromol L(-1)), capsaicin (1 micromol L(-1)) or L-NAME (100 micromol L(-1)), suggesting that neither nerves nor nitric oxide pathways were involved. These data demonstrate that STW 5 profoundly alters gastric motility in a region-specific but not layer-specific manner and thus implicates Iberogast in the treatment of FD patients suffering from motility disorders with impaired fundus accommodation and/or antral hypomotility.